Crystal matrix



N. ROCHESTER CRYSTAL MATRIX July 12, 1949.

4 Sheets-Sheet 1 Filed May 6, 1948 p h 5 we Z 0 w m E a m ww N RECTIFIER MHT'R/X ZZzza.

SWITCH July 12, 1949. N. ROCHESTER CRYSTAL MATRIX 4 Sheets-Sheet 3 Filed May 6, 194a INVENTOR. q. [Vatbaniel [Zea/Jester July 12, 1949.

4 Sheets-Sheet 2 Filed May 6, 1948 Emu r QWN QNN a W me n R W l 2 .m 9W4 J WW4 wmwm July 12, 1949. N. ROCHESTER 2,476,066

CRYSTAL MATRIX Filed May 6, 1948 4 Sheets-Sheet 4 Z56 g INVENTOR.

@ A/albarnl Rochester a BY fitter/reg Patented July 12 1949 Nathaniel Rochester, Milton, Mass., Sylvania Electric Products Inc., a

of Massachusetts assignor to corporation Application May 6, 1948, Serial No. 25,432

7 Claims. (Cl. 177-353) The present invention relates to rectifier natrices that are employed for switching purposes.

In a known class of rectifier networks, the selective terminals of a number of two-position switching devices in an equal number of, channels can be caused to render effective one line of a plurality of lines (not greater than two raised to a power corresponding to the number of channels) the efiective line dependin upon the combined setting of all the switching devices. The rectifier matrix is sometimes regarded as a .form

2 channels, respectively, switching devices.

In Fig. l rectifier matrix I has multiple indihaving two-position vidual lines l2 emerging which are jointly ener-.

' nected to one of each of switching matrix because it can variably route signals between a number of channels, or sets (usually pairs) of lines taken in varied permutations, and a larger number of individual lines. As a routing switch, the rectifier matrix is notable for its high speed of achieving the desired circuit conditioning.

The rectangular matrix and the pyramidal matrix, as known forms of matrices are kno wn,

are limited as apractical matter to a relatively modest number of channels. An object of the present invention is the simplification of rectifier matrices and the improvement of their performance. Moreparticularly, an object of this invention is to provide a rectifier matrix requiring a minimum number of rectifiers for achieving the desired selective interaction between a large number of individual lines and a multiplicity 01 channels having paired oppositely'conditioned lines. 1

The nature of the invention,,- litsj application,

; and further objects and features'of. novelty will 5 be better appreciated from the following detailed idisclosure including several embodiments of the invention. In the drawings:

1 Fig. 1 is a block diagram'to aid'i n describing a" variety of uses of rectifier matrices; 1 Fig. 2 is a wiring diagram of a three-channel, i eight-line rectangular rectifier matrix;

Fig. 3 is a wiring diagram of-a five-channel,

. thirty-two line matrix embodying certain aspects of the present invention; 7 v 1 Figs. 4a and l are symbolicdiagrams of the hnown five-channel matrices, representing -respectively the pyramidal form and the rectanguadditional novel five-channel matrices using the same symbolic notation; i Fig. 5 is the wiring diagram of a'four-channel,

lar form, while Figs. 4b-k arediagrams of various mg. 6 is the symbolic diagram of'the'matrix in energized- Allthe units at other times. 40

gized-by a voltage source l4 through impedances l6. Only four impedances are shown, additional ones being indicated by the dotted lines. Muitiple'channels l8 (only three of which are shown) are extended to includes pairs of wires 22cc, 2241b, f22ba, 22bb, etc. One channel 18 is conpair of wires 22 by two-position switching devices 24. These may be simple mechanical switches, operated manually or by re-' lays or motor-operated cams, or they maybe electronic devices such as scale-of-two counters; in such manner that wires 22a and 22b are diiierently conditioned electrically. Normally one wire of each pair is energized while .the other is not. but both wires may be energized in a distinctively different manner. The mechanical or electronic operation of switching devices 24 is efiected by switch control 25.

The rectifier matrix has various uses. For example, voltage supply may be a bias battery and units "5 maybe bias resistors for electronic tubes (not shown) where the tube in only one line isto be allowed to conduct space current for a unique permutation of positions of switching devices 24. "This finds application in digital computers. In another use voltage source E may be simply a signal receiver where a pulse is received at a critical time within a cycle, and switches 24 are operated to assume all possible combination sequentially during the cycle of source l4. Under the circumstances when the pulse is received, all units l6 except the one to be selected corresponding to the timing of the pulse will be I6 will be deenergized This system is applicable to multiplex communication. In a further application it is possible to deenergize one circuit l6 and discover the combinational setting of switching devices |4 corresponding to the individual control selection l6 by cycling switching devices 24 until all channels iii are simultaneouslyenergized or simultaneously deenergized. Novel forms 01f rectifier matrices rather than uses of such matrices application. The foregoing uses are illustrative. i

The manner in which the rectifier matrix achieves the foregoing'results will be appreciated from a study of Fig. 2 wherein three channels I ll are arranged in a rectangular matrix for-selectivev r matrices employing a. minimum of rctifiers m fhandling 16 and 256 lines with four and eight" connection to eight individual lines H2. (Where feasible, the parts in Fig. 2 bear the same numbers as in Fig. l, with added.)

In Fig. 2 channel I l8a is alternatively switched to wire I22aa or I22ab; and each wire is joined to like terminals of four rectifiers 30, while the rectifiers are connected at their opposite'terminals to different ones oi. the eight lines I I2. (Rectifiers 30 are individually designated by the lower case and upper case characters corresponding to the associated channels I I3 and individual lines II2.) Channels II3b and H80 are similarly connected through switching devices, wires and dual sets of rectifiers to lines II2. Each line has three rectifiers joined to it, the distribution of the rectifiers being difierent for the different channels to the end that one line II2 will be deenergized for a given settin of the three switching devices I24, and different lines II2 will be deenergized for different permutations of alternatively energized paired wires I22. Channels Illa are all energized and suitable return circuits are provided for lines II2A, H23, H20, etc.

With the switching devices in the configuration shown, it will be apparent that lines 21:,

- II2F, II2G and 21-1 will not be energized by channel to since line I22ca is not energized.

However, lines I I2G and II2I-I are energized by connection of line II3b to line I22bb. Channel' ,I I8a, connected to lines I22ab energizes line I I2F and line I22H (which is already energized by line I I8b). Line I I2E it will be observed, is not ener gized, Lines II2A, H23, H26 and II2D are all energized byv channel 30 through line I22cb. Rectifiers are joined to lines II2 A H and to wires I22, with terminals of like polarity connected to those lines and wires respectively, as

shown in the wiring diagram. But for'rectifiers 30, terminal II2E would be energized by its;connection to lines I22aa. I22ba and I22ca to which the energized lines H2 are variously connected. Where rectifier 30Ac is polarized properly to conduct current and thereby energize terminal I I2A,

rectifier 30Aa would then be a barrier against energization of line I22Aa via rectifier 30Ac. Similarly rectifiers 300a and "Ga are also reversely polarized with respect to the current that might pass through rectifier 30Ac. Likewise, rectifiers 30Ab, 3013b and 30F!) prevent energization of line l22ba, and rectifiers 30Hc, 30Gc and 30Fc prevent energization of line I22ca. With'the connections shown, it is possible to set switching devices I24 in various combinations so as-to have a single line II2 deenergized for each different. combinational setting of those devices.

Rectifiers 30 may take various forms such as the vacuum-tube diode or the barrier type exemplified by germanium crystal rectifiers. Barrier rectifiers exhibit very high back resistance, ordinarily lower than that of the vacuum-tube diode, but they do conduct to some extent during application of reverse polarity. For this reason it is important to analyze the rectifier matrix to discover whether the back resistance of the rectifiers materially modifies the results describedabove for ideal blocking rectifiers having infinite I back resistance.

gized when two-position with each other, and the circuit resistance connected to lines I I2 should also be taken into account. I

The parallel back'resistance oi the rectifiers may be acceptable for the three-channel, eightline rectangular matrix as shown. It will be observed that each line I I2 has three rectifiers connected to it. Where four channels I I3 are to be joined in a rectangular matrix to lines I I2 (which then may be 16 in number rather than 8) four I rectifiers 33 would be connected to each line H2, and each of these'four would be a member of a group of eight, the others of which would exhibit back resistance, and consequently the back resistance of the rectifiers is reduced to /18 of that of a single rectifier in accordance with the expression Rb/1l(2 -1).. A four-channel rectangular matrix is shown in Fig. 5.

In the rectangular rectifier matrix the number of connections, the number of rectifier elements, and (especially where the back resistance of the rectifier is significantly low), the number of parallel blocking rectifiers greatly increases, with resulting decreased back resistance and poorer descrimination between the selected line and the others. In one aspect of thepresent invention the back resistance characteristic of large matrices using a given type of rectifier is to be improved. This is generally achieved byholding the number of rectifiers connected to any one form of rectifier matrix for selecting one line among thirty-two lines 2I2 which will be deener- 224a-e in five channels ,2I8a-e are set in any definite pattern. (In Fig. 3, the same numbers are used as inFig. Zwhere convenientto represent like parts, with added.) There are fivechannels 2I3 each of which selects either one or the other of a pair of wires 222, which select {one line among 2 :32 individual lines 2I2. Thisis char acteristic of rectangular and pyramidal matrices as well asthe novel matrices. However, the thirfty-two line rectifier matrix of the rectangular variety would normally utilize five groups of thinty-two rectifier units each, or a total of rectifiers. The novel matrix illustrated in Fig. 53

employs two groups 232 and 234 of thirty-twin rectifiers each, and in addition thirty-two rect fiers arranged in other groups (to be describe for a reduced total of only 96 rectifiers and a. reduction in bulk, in number of circuit conn tions and in paralleledback-resistance rectifi r circuits, as will appear.

Each line 2I2 is oonnectedto one in one of the'groups 232, 234 is higher than int'he case where that rectifier is effectively in parallel with multiple other rectifiers that are also n-, nected to that line 2I2 as in,the case of the'r tangular matrix. I 2

Rectifiers 230 in group 232 are divided into 1 ur sets of eight rectifiers each. The sets have wires 236--239 that may be regarded as a four-wire set oi lines, where one line can be selected by a bordinate matrix 240. This matrix has a rect fier group 242 having four rectifiers dividedinto' wo sets 242a and 24212 of two rectifiers each, and another rectifier group 243 having four rectifiers lso divided into two sets 243a and 2432) of two r ctiswitching devices rectifier 233 l in each of rectifier groups 232 and 234. 'It is I apparent that the back resistance of arectifier 5, fiers each. The combind settings of switching devices 224a and 2242) in two of the five channels 2! are effective to select one wire of the four wires 236239.

Group 234 of 32 rectifiers 230 is divided into eight-sets of four connected rectifiers each, the like terminals of the several sets being connected to one of the wires 244-25 I. Subordinate matrix 256 including rectifier groups 252 and 254 is effective to select one of the eight lines 24425l for its effect on rectifier group 234. The two selected sets of rectifiers, one in each of groups 232 and 234, combine to select a single line 2l2.

Group 252 of eight rectifiers connected to lines 244- 25l is divided into two sets 252a and 25212 which are connected to wires 2220a and 2220b. Only one of these wires is energized by switching device 2240 in channel 2l8c.

Group 254 of eight rectifiers also connected to lines 244-25l is divided into four sets of rectitiers which are connected to a further set of wires 258, 259, 260 and 2H. One of the wires 258-2BI is selected by an eight-rectifier matrix 262 under control of two channels HM and 2l8a just as in the eight-rectifier matrix 240 controlled by channels 2l8a and 2l8b.

Fig. 3 may be compared to a symbolic representation of the same matrix in Fig. 4f. There the triangle 300 represents the thirty-two individual lines of Fig. 3. The first two squares 332 and 334m the column adjacent the triangle represent rectifier groups 232 and 234. Two arrows join the triangle with square 332. These represent the combined selective effect of channels 2| 8a and H817. Circles 342 and 343 to the right of square 332 represent rectifier groups 242 and 243, and are joined by one arrow each to that square. The arrows represent the separate channels 2l8a and 21%. Square 334 is linked to the triangle by three arrows to represent the combined effect of channels 2l8a, 218d and 2l8e in selecting a single line 2l2. To the right of this square is a further square 354 and a circle 352. This square is joined to square 334 by two arrows to represent the combined effect of two channels H811 and 2I8e while the circle'is joined to square 334 by a single arrow to represent the single control effect of channel 2l8a. The separate control effects of channels 2l8a and 2l8e are combined in square 354 by a pair of four-rectifier ally exerting their effects just as in the case of the two channels combined in square 332.

It will be observed that the squares in the column to the right of the triangle both include the numeral 32, which equals the 32 rectifiers in groups 232 and 234. Each of the circles to the right of square 332 contains the numeral 4 which equals the number of rectifiers in each of groups 242 and 243. The enclosures in the single vertical column to the right of square 334 both inciude the numeral 8, which equals the number of rectifiers in group 252 and in group 254. The circles in the extreme right column joined by arrows to square 354 both include the numeral 4 which equals the two groups of four rectifiers each in matrix 262.

The symbolic notation may be generalized. Within a triangle the number represents the maximum number of lines accommodated. The arrows leaving the triangle represent the number of channels of the power n to which 2 is raised to give the number of lines in the triangle that can be uniquely related to n two-wire chan- 'nels. Where a single arrow terminates in an groups represented by circles 362 and 364 severenclosure, that enclosure is a circle and no arrow leaves it. Where multiple arrows leave the triangle toward a common enclosure, that enclosure is a square and must be further subdivided into squares and/or circles until individual arrows terminate in individual circles. The number written in a square or circle is 2 where p is the number of arrows leaving the previous enclosure. The total number of two-terminal rectifiers needed to form a matrix is the sum of the numbers in the squares and circles.

Applying the foregoing rules to Fig. 2, it will be readily apparent that the triangle should have "8 within it to represent the eight lines H2 accommodated. Three arrows should be drawn separately to three circles each of which should contain the numeral 8 since three arrows leave the previous enclosure and 2":8. The total number of rectifiers required for this matrix is 24, which is correct as will be seen in Fig. 2.

The symbolic diagram as noted above gives the final number of lines 2* from which one selection is to be made by proper conditioning of p two-position switching devices; it gives the total number of rectifiers in each group of rectihers and the number of groups of rectifiers in any stage of resolution; the total number of rectifiers required; and in fact it gives complete information on the actual wiring diagram. Three parallel arrows reach square 334, which therefore yields 2 :8 wires, and requires the 32 rectifiers to be divided into eight sets. Two parallel arrows reach square 332 which therefore yields 2==4 wires, and requires the 32 rectifiers to be divided onto four sets. A pair of parallel arrows and a single arrow diverge from square 334 to square 354 and circle 352, which consequently yield 2 :4 wires and 2 :2 wires, respectively, and corresponding subdivisions of the rectifier groups into two and four sets is required.

Using the symbolic diagram technique thus expounded, it becomes quite simple to draw all the possible matrices having 32 lines selectively associated with five two-wire channels, and this has been done in Fig. 4. In Fig. 4a there is shown the five-channel pyramidal matrix, wherein n1=4 stages of resolution are required. In any one stage only one channel is combined with previously combined channels; or, viewed otherwise, each stage of resolution separates one channel from the remaining combined channels. The number of rectifiers is less than in the rectangular matrix, but by no means a minimum. Furthermore, the back resistance of the rectifiers in the network (especially significant with barrier rectifiers) is not utilized to best advantage (depending somewhat on the associated circuits) even though no more than the minimum of two rectifiers are connected to each line yielded at any stage of resolution; for the multiplicity of stages reduces the advantage of providing a minimum number of parallel back-resistance paths in any one stage.

The remaing parts of Fig. 4 show all other five-channel matrix possibilities. Figs. 4a and I have been described. Fig. 41 represents the onestage resolution characteristic of the known rectangular form of matrix and requires by far the largest number of rectifiers and attendant number of connections, bulk and number of back-resistance paths. Fig. 4g uses the same number of rectifiers as Fig. 4f, utilizing the same resolution down to the three channei level. Itis known that, for three channels, the rectangular matrix and the rectangular matrix are alike in rectifiers be seen by drawing all possible four-position and .eight position networks.

' i n outline and then in detafl. Step 1.-Divide the class N(n) into two mutu anaoee required. Figs. 4! and a are the most economical ciude matrices having the multiple-stage char- 5 acteristic oi the pyramidal matrix without adhering to the pyramidal matrix limitation of combining no more than a single channel with previously combined channels at one stage; and the possibilities include matrices having the rectangular characteristic of combining three or more separate channels or groups or channels in one st e. It will be 4 shown that the most economical matrix from the viewpoint of the number of rectifier units required can be directly determined by dividingthe number'of arrows leaving'the previous enclosure in two groups each terminating in an enclosure, where the number of arrows is greater than 3; and by making the-numbers oi arrows in these groups as nearly alike as possible.

In terms of circuits this means that no more than two groups of rectiflers are to be connected to any mm) defined in'the proo Then demonstrate that NaQn) =E(n) (3) Step 3.-Demonstr'ate that N401) EO) (4;)

thereby proving inequality (1) since the class N(n) includes only the mutually exclusive subclases N1(n) mm), and Ndn).

Before carrying out these three steps one other thing should be done. It happens that inequality (1) calls for experimental vertification for all values of n which are lessthan or equal to 6. This was performed by drawing each oi. the shorthand diagrams for the various values of E(n) given in Fig. 7 for four channels. and Figs. 41 and g for five channels; and considering the consequences irom the rules tor set of lines in which more than three channels are combined (indicating that only two rectifiers, one from each group, are connected to any one line in stages that combine more than three channels); and the rectiflers of each group are to be divided into two times 2 equal sets where p is the number of channels having input wires connected to the group of rectifiers. This can be verified for the case in the thirty-two line. five-channel matrix in Fig. 4. In Figs. 4a to e, the division of the arrows leaving the triangle is four andone, an unequal split. In Figs. 4h to l, the division-is into more than two-groups- Figs: 41' and 4 comply with the stated rules, and are most economical. Figs. 4b, 4c, 4d and 4e are alike in the first stage 01' resolution. In the further subdivision of four channels, Fig. 4c is most economical. Fig. 4b incorporates an unequal split and Figs. 4d and 4e subdivided into more than two groups. These rules for the most economical matrix from the viewpoint of number of rectiflers required can be proved mathematically (1) Let N(n) be a function of the positive discrete variable n and let it be equal to the numselects one from 2 positions. Notice that when n 3, N(n) has several values for any value of n. The interpretation here to be used is that mm represents any one of its possible positive values.

Mal na) (1) Only one four-postion network can be drawn,

and the two possible eight-position networks each require the same number of rectiflers. This can Because the proof is so involved, it will be given 1y exclusive sub-classes N101) and Na(n) defined in the roof. Then demonstrate that Step 2.--Divide the subclass moo into two mutually exclusive sub-sub-classes moo and ber of rectifiers needed to make a network which v which would have .resulted fom any deviation drawing the most economical network.

, In the following table there are listed the values of E(n). derived by drawing diagrams of all matrices conceivable and selecting the most economical ones which proved to be in accord with the rules stated, while all matrices not in accord with the rules required a greater number of rectifiers. Fig. 8 shows'the most economical eight-channel matrix, drawn in accord with the stated rules.

2 a 4 s 12 a 24 s is 24 4 4s 1s 32 4s 5 9e 32 64 as e 176- 64 123V 122 1 32s '12s 25a -as4 a 608 256 512 m 9 1, 168 512 1,024 1, 536 10 2,240 1,024 2,048 3,072 11 4,368 2,048 4,096 a, 144 12 8,544 4,096 8,192 12,38

In the table it is apparent thatEtn) seems to approach 2-2 as 12 gets large,- but that Em) is greater than 2-2. when n is greater than 2. This is true because 2-2 rectifiers areneeded to at-- tach two rectiflers to each line, and attaching at least two rectifiers is necessary but not adequate.

From the table it can be seen that Ein) is equal to or less than 3-2", at least up'to n=12.

Step 1.In' order to define the sub-classes N101) and mm) reference is had to the shorthand notation. Let N201) represent the number of rectifiers needed to make any network for which the shorthand notation showsthe arrows from the triangle going to two andlonly two enclosures. Let N1(n) represent, the number of rectiflers. needed to make any other network. (In other words let Nun) represent the number oi rectifiers needed to make a network for which the shorthand shows the arrows from the triang going to more than two enclosures.)

It is evident from the shorthand that 3 mm) .3 2 5 (s) This is so because each group of arrows from the triangle to an enclosure represent 2' rectifiers and there are at least 3 of these groups.

It is also evident for much the same reason that 2-2"+2-E(n/2), when n is even when n is od next greater value r+l.

not/2) is the single-valued function which corresponds to the number oi rectifier-s needed to "make an n/2-position rectifier network by ollowing the rules given for designing the most economical network; (two n/2-positionnetworks are needed for further resolution of 2 lines into 1: channels after the first step or resolution that has two groups of 2" rectifiers) and Q are similarly the number of rectifiers needed for the further resolution of the network where n is will be demonstrated bythe method of mathematical induction.

Proof that inequality (1) holds at least when n tion of the first half of the table above.

It may be assumed tentatively that inequality meaning that there should be a resolution into two groups of rectifiers and not more at any stage of resolution above the three-channel level for the most economical network.

is less than or equal to 6 comes from an inspec-' (8) is true for all values of n which are less than v or equal to a particular value designated as 1'. Now it will be proved that, if r is greater than or equal to 6, the inequality holds for the next value ofnwhichisr+1.

This proof will be carried out first for odd values of r+1. Inserting this value in Equation 6:

' Now inserting inequality (8) into Equation 9: E(1'+1) --2-2+ +(3-2' +3-2' (10) Notice that whenever r is greater than or equal to 6 inequality (10) canbe rewritten as:

because 4 1-2'+ s-2' +s-2' when r 6. (12) therefore E(r+1) 3-2'+ for 1 6 (13) The same expressions can be rewritten for the 7 case when 1+1 is even.

E(r+1) =2.2'+ +2.E(% (1'4) and, from ('i). I

E(r+ 1 g2-2'+ +2-2-2 (15) Wherefor v v I E(r+1) 3-2 when r 3 (16) because i 2+ 22-2-2 2 when r23 (17) Therefore, by mathematical induction for all positive integral values of n. The smallest admissible value of the integer has been verified by the table, and it has'been' shown that, if the theorem is true for one value r, it is true for the Together inequalities Next to be proved is that the division of arrows between the squares should be as even as possible for best economy above the three-channel level. This is done in two stages. The first stage (step 2) will prove that the division must be within one arrow of being as even as possible, and in the second stage (step 3) the case of division which is as even as possible will be compared with the case which differs by one arrow Step 2.-It will be proved that the division of arrows must be within one arrow of being as even as possible for the case of even numbers and then for odd numbers.

If n is an even number and if an even division If an uneven split is made Notice that a v i moo s m ii m s 1 (24) because I Next consider the case in which it is an odd number. If the most nearly even'division is m de t Substituting inequality (5) in Equation 26 and enlarging one term Em 52-2-+2 a-2 2 If a less even division is made in which m 2 and mm) as the rest of the values (5) and (18) demonstrate that I N1(n) EO!) (19) and because V Ni (n) a-2 where n 3 (2o) Rewriting (30) and combining with (24) Ns(n) E(n) (32) Consider four cases.

. In the first case, let

j n=4p (33) v For the even division write E(4p)=2-2 +2-2- 2' +4E(p) While the odd divisiongives It is then'obvious that E011?) N(4p) when p l (39) channel matrix have been regarded as required.

However, it is perfectly sensible in some cases to dispense with certain of the total possible lines;

' for this invention applies equally to those matrices where all the possible lines are utilized as where certain of them are disregarded. An im-- portant aspect of the invention resides in the provision of the most economical matrix or matrices, as the case may be, for any number of input channels; but the other novel matrices are of like importanc in special circumstances, as where symmetry, interchangeability of submatrices, and relation of back resistances to resistances in the circuits associated with the matrix.

In some parts of this disclosure the paired wires are termed input wires or input" channels and the individual lines are termed output" lines. These terms are in accord with the usual relations, but are used for convenience and not to restrict the matrix circuits to such use as against the reverse translation where the input may appear at the individual lines. 1

Varied modifications and applications of the novel aspects of the foregoing disclosure will occur to those skilled in the art; and it is therefore fitting that the appended claims be given broad interpretation, consistent with the spirit and scope of the invention.

What is claimed is: 1. A rectifier matrix having 2 lines and n twowire channels where n is any positive integer,

greater than 3, said matrix being successively reduced from 2 lines to n channels by a net,-

work including pairs of rectifiers having like terminals connected to said lines, said rectifiers being divided into two groups, the remaining terminals of the rectifiers being joined in equal sets of 2 in one group and 2 of the other group where k and m are positive integers totaling n.

and m and k are as nearly equal as possible.

possible.

3. A matrix having 2" individuailines and 1. pairs of wires such that combinations of the wires in alternative conditions will be uniquely related 12 to difierent ones of the lines, said matrix havin only two rectifier groups connected to said lines withone rectifier of each group having a like terminal Joined to each of said lines, there being 2 rectifiers in each group, each of said rectifier groups being Joined at their opposite terminals to constitute plural'pairs of rectifier sets, and further groups of rectifiers connected to said pairs of sets for iurther resolution or said wires into unique relationship with said individual wires.

4. A matrix having 2 1 individual lines and n pairs of wires such that combinations of they wires in alternative conditions will be uniquely related to different ones of the lines; said matrix including two rectifier groups with 2 rectifiers in each group, the rectifiers of each group having like terminals l'oinedto each of said lines, each of said rectifier groups being joined at their opposite terminals in plural pairs ofsets, and further groups of rectifiers .connected to said pairs of sets for further resolution of said paired wires into unique relationshipv with said individ-- ual lines. I

5. A matrix having a group of individual lines connected in a networkto plural sets of wires, one of said lines being electrically distinctive from the other lines, one wire of each set, of wires being similarly distinctive, said matrixincluding two groups of rectifiers, one rectifier in each group being connected at a terminal of one polarity to one of said individual lines, the other rectifiers of each group being similarly connected to others of said lines, the rectifiers of each group I being-joined at their terminals of opposite terminals into plural pairs of sets, one or each of said wires being connected to a respective one of said rectifier sets.

6. A rectifier matrix, of which 2 -lines are re-- solved into n two-wire channels, where n is any integer greater than 3, said matrix comprising a network including pairs of rectifiers having like terminals connected to said lines, said rectifiers being divided into two groups, the remaining terminals of the rectifiers being joined in sets lines up to 2 where n is the number of associated two-wire channels, comprisingrectifien submatrices embodying both rectangular and pyramidal matrix characteristics.

NATHANIEL ROCHESTER;

REFERENCES CITED The following reierenices are of record in the file of this patent: 1

UNITEDSTATES PATENTS Number t I I OTHER REFERENCES Ser. No. 108,062, Toulon May 18, 1943.

(.A. P. 0.), published 

